Netwkork planning traffic measurement program

ABSTRACT

In a public switched telephone network, real time monitors on SS 7  links will collect interoffice signaling messages. A site processor compiles data from the signaling messages relating to individual calls, to form call detail records (CDRs) for all interoffice call attempts. The site servers upload the CDRs to a central server. Automatic Message Accounting (AMA) records also are accumulated for at least selected central office switching systems and uploaded to a server. Programs running on the servers enable network operations personal to analyze a variety of network traffic patterns, for example to study the number of calls to particular numbers during various times periods and the hold time of the calls in order to identify the numbers of Internet Service Providers (ISPs). As another example, the traffic analysis may indicate the amount of traffic between two end offices and the percentage thereof routed through a tandem office, to allow network planners to design trunk upgrades between the various offices and/or to plan the addition of new offices.

TECHNICAL FIELD

[0001] The present invention relates to a method and system foranalyzing a variety of network traffic patterns to permit networkplanners to design trunk upgrades between various offices and/or to planthe addition of new offices.

ACRONYMS

[0002] The written description uses a large number of acronyms to referto various services, messages and system components. Although generallyknown, use of several of these acronyms is not strictly standardized inthe art. For purposes of this discussion, acronyms therefore will bedefined as follows:

[0003] Address Complete Message (ACM)

[0004] Advanced Intelligent Network (AIN)

[0005] Asynchronous Digital Signal Line (ADSL)

[0006] ANswer Message (ANM)

[0007] Automatic Message Accounting (AMA)

[0008] Automatic Number Identification (ANI)

[0009] Call Processing Record (CPR)

[0010] Call Detail Record (CDR)

[0011] Central Office (CO)

[0012] Certified Local Exchange Carrier (CLEC)

[0013] Common Channel Interoffice Signaling (CCIS)

[0014] Comma Separated Values (CSV)

[0015] Data and Reporting System (DRS)

[0016] Engineering Data Acquisition System (EDAS)

[0017] Executive Information System (EIS)

[0018] Destination Point Code (DPC)

[0019] Fiber Distributed Data Interface (FDDI)

[0020] Generic Data Interface (GDI)

[0021] Initial Address Message (IAM)

[0022] Integrated Service Control Point (ISCP)

[0023] Integrated Services Digital Network (ISDN)

[0024] ISDN User Part (ISDN-UP)

[0025] Intelligent Peripheral (IP)

[0026] Internet Service Provider (ISP)

[0027] Line Identification Data Base (LIDB)

[0028] Message Processing Server (MPS)

[0029] Multi-Services Application Platform (MSAP)

[0030] Office Equipment (OE)

[0031] Online Analytical Processing (OLAP)

[0032] Origination Point Code (OPC)

[0033] Personal Area Network (PAN)

[0034] Personal Communications Service (PCS)

[0035] Plain Old Telephone Service (POTS)

[0036] Point in Call (PIC)

[0037] Personal Identification Number (PIN)

[0038] Primary Rate Interface (PRI)

[0039] Public Switched Telephone Network (PSTN)

[0040] Release Complete Message (RLC)

[0041] Release Message (REL)

[0042] Revenue Accounting Office (RAO)

[0043] Service Control Point (SOP)

[0044] Service Creation Environment (SCE)

[0045] Service Management System (SMS)

[0046] Service Switching Point (SSP)

[0047] Signaling System 7 (SS7)

[0048] Signaling Point (SP)

[0049] Signaling Transfer Point (STP)

[0050] Simplified Message Desk Interface (SMDI)

[0051] Speaker Identification/Verification (SIV)

[0052] Terminating Attempt Trigger (TAT)

[0053] Time Slot Interchange (TSI)

[0054] Traffic Service Position System (TSPS)

[0055] Transaction Capabilities Applications Part (TCAP)

[0056] Transmission Control Protocol/Internet Protocol

[0057] (TCP/IP)

[0058] Wide Area Network (WAN)

BACKGROUND ART

[0059] An essential problem in optimizing a telecommunications networkis balancing equipment and trunking against service and cost. Networkdesign involves predicting future demand based on past results,evaluating the capacity of equipment and facilities, and providing thecorrect amount of capacity in the proper configuration, in time to meetservice objectives. Since virtually every element of atelecommunications system is subject to failure or overload effectivetesting, monitoring, control, and maintenance is essential to obtain anacceptable level of performance.

[0060] U.S. Pat. No. 5,475,732 issued to Eugene Pester Dec. 12, 1995,for Common Channeling Signaling Network Maintenance and Testing,describes an SS7 Network Preventative Maintenance System for detectingpotential SS7 and switched network troubles, automatically analyzing thetroubles, and providing alarm and corrective action to avoid majornetwork events. The Pester SS7 Real Time Monitor System described inthat patent is a multi stage SS7 network preventative maintenance toolthat detects potential SS7 and switched network troubles, automaticallyanalyzes those troubles, and provides alarm and corrective actioninstructions to maintenance personnel in time to avoid a major networkevent. This is accomplished by placing real time SS7 monitors on linksat the Signal Transfer Points (STPs).

[0061] Information on exceeded Link Load, exceeded Message SignalingUnit (MSU) frequency and Network Management status/error conditions ispassed to a Stage 1 controller or process. The Stage 1 process controlslink monitors capable of monitoring upwards of 32 link monitors at asingle STP. The monitors perform preliminary link analysis on errorconditions. If the monitors identify trouble on any of the links, alarminformation is sent to a Stage 2 controller or process via the Stage 1process. The Stage 2 process controls all Stage 1 and associatedmonitors from an STP pair. If Stage 2 determines that there is an STPpair network trouble, it generates alarm and corrective actioninformation and passes it to the Stage 3 controller or process. TheStage 3 process controls all Stage 2 controllers or processes in theoperating company. If Stage 3 determines that there is potential or realcompany network trouble, it generates alarm and corrective actioninformation and display signals on maintenance terminals in thecompany's SS7 control center (SEAC, SCC, etc.). Stage 3 also alerts theStage 4 controller process.

[0062] U.S. Pat. No. 5,592,530 issued to Brockman et al (Brockman) onJan. 7, 1997 for Telephone Switch Dual Monitors, relates to testing andmonitoring systems for evaluating the operations of telephone switchesand more particularly to monitoring systems which are arranged tocapture data between nodes of a telephone switching system where thedata flows between mated nodes, as in an SS7 common channel signalingnetwork. The Brockman Patent uses the term “telephone switches” to referto service transfer points (STPs) in the SS7 network.

[0063] The patent indicates that an SS7 network can be thought of as aseparate switching system which is used prior to, during, and at the endof calls for the purpose of routing control information. Whenever twoswitches or elements in the SS7 network have to pass call controlinformation to one another during or prior to a phone call, they passthis data via the SS7 network. The patent describes an SS7 network astraditionally having three basic types of network node elements. Theseare listed as the Service Switching Point (SSP), which may be a centraloffice, tandem or end office switch, a Service Control Point (SCP), anda Signal Transfer Point (STP), which is described as essentially apacket switch which routes the messages from SSPs and SCPs to SSPs andSCPs.

[0064] The SS7 network is stated to be critical to operation of thetelephone network and to require the deployment of “surveillanceequipment to monitor the links connecting the nodes of the SS7 network.”The patent describes the topology of the SS7 network as such that STPsare deployed in a mated pair configuration at geographically separatelocations. A set of SSPs and SCPs will be connected to a mated pair ofSTPs. This conglomeration of SSPs, SCPs, and mated pair STPs is called acluster. Clusters are then connected by D-QUAD links between STP matedpairs.

[0065] The patent indicates that it is often the case that the messagesgoing from switch A to switch B travel one route on the network, whilethe messages going from switch B to switch A travel a different route.The network surveillance equipment that monitors the link is designed tocapture and correlate as much signaling information as possibleregarding network activity. Because of the different paths that messagesmay take, data relating to a subscribers phone number may be all in oneSTP, or split partially in one STP and partially in the other STP of themated pair “which may be in a different city.”

[0066] The patent postulates that what is needed is a “distributed statemachine that can capture all of the SS7 messages within a mated paircluster and correlate the fragmented SS7 messages pertaining to aparticular call or transaction to a single data record.” The patentfurther states that what is needed is a filtering of redundant orunnecessary SS7 messages in order to compile call transaction recordscontaining a minimum amount of essential data in order to evaluateoverall system performance and to diagnose system errors when theyoccur.

[0067] The patent indicates that “the ability to capture all of the SS7messages within a mated pair cluster and correlate the fragmented SS7messages makes other improvements to telephone network servicespossible. In addition to the performance monitoring applicationsoutlined above, there is a need for systems which are capable ofgenerating call detail records from the SS7 messages of a mated paircluster for use in billing systems and to implement a fraud detectionsystem for certain types of telephone calling cards.” The patent goes onto indicate a need for telephone monitoring systems which enable a userto implement a call trace mechanism that can track all SS7 messagesassociated with a particular phone number in order to retroactivelytrace harassing or obscene phone calls.

[0068] Additionally, it is stated that there is a need for a telephonemonitoring system which can monitor the SS7 messages of a mated paircluster in order to implement what is called “mass call onsetdetection.” This is stated to be useful in circumstances where a largenumber of callers attempt to call a single phone number at the sametime, such as where radio stations give away prizes to callers who callin immediately, thereby creating a mass call-in. It is indicated thatmass call onset detection applications detect the situation early as thenumber of SS7 messages pertaining to a particular phone number increasesrapidly and alerts the phone company quickly to the large number of busyconditions associated with a given phone number.

[0069] In summarizing its description the patent states that themonitoring devices “key off the links to the SS7 itself, so that alldata on the SS7 circuits entering the STPs are monitored.” However, alevel of filtering is provided to capture only the data which isnecessary for providing call detail records. The STP is stated to be thecentral routing point for the SS7 data. Monitoring devices are connectedby a communication link that enables the monitoring devices to track andcorrelate all the SS7 data at an application layer in a distributedfashion across two STPs. From this one can determine error conditions atthe application layer of the network. It is also possible to generateinformation that could be used for fraud detection and could generateanother level of call detail records.

[0070] While the above discussed Pester and Brockman et al patentsdescribe the usefulness of monitors in an SS7 common channel interofficesignaling network for event detection, neither of these patents isdirected to the particular problems addressed by the present invention.The Pester patent places emphasis on monitoring of the SS7 networkitself in order to detect troubles in its functioning. SS7 link monitorsare utilized on each SS7 link in the illustrated depiction of thatsystem. The Brockman et al patent focuses on monitoring of all links tothe STPs in a pair and the assembly of related SS7 signaling messagescomprising a record of call completions.

[0071] While these methodologies may be effective for their statedpurposes there remains a distinct need for an efficient and effectivetool for coping with the types of traffic and billing problems which arepresently associated with overload of trunk circuits to Internet ServiceProviders (ISPs) and to Competitor Local Exchange Carriers (CLECs).Attempts to use other more traditional approaches, such as the switchesthemselves and the Engineering Data Acquisition System (EDAS), fellshort of providing the desired information.

[0072] It is accordingly an object of this invention to provide arelatively low cost solution to those problems. While two specificproblem situations are mentioned as typical for ease of description ofthe invention, it is to be understood that those problems are to beregarded as examples only, as the invention is applicable to a widevariety of related problems.

[0073] It is another object of the invention to provide a timely,powerful, cost effective means of analyzing traffic on the PublicSwitched Telephone Network (PSTN).

[0074] It is a further object of the invention to provide a flexible,expedient, accurate, and cost effective method to identify individualhigh usage lines contributing to network blockage.

[0075] It is another object of the invention to provide a tandem trunkplanning resource which will accommodate future tandem switch growthrespondent to customer calling patterns, communities of interest andpoints of origin and destination.

[0076] It is yet another object of the invention to implement InternetService Provider (ISP) studies and enable better service to ISPcustomers while maintaining optimal network utilization.

DISCLOSURE OF THE INVENTION

[0077] The present invention utilizes real time monitors on selected SS7links to collect interoffice signaling messages. A site processorcompiles data from the signaling messages relating to individual calls,to form call detail records (CDRs) for all interoffice call attempts.The site servers upload the CDRs to a central server. Automatic MessageAccounting (AMA) records also are accumulated for at least selectedcentral office switching systems and uploaded to a server. Programsrunning on the servers enable network operations personnel to analyze avariety of network traffic patterns. One example is to study the numberof calls to particular numbers during various time periods and the holdtime of the calls in order to identify the numbers of Internet ServiceProviders (ISPs). Another example would involve a situation wheretraffic analysis may indicate the amount of traffic between two endoffices and the percentage thereof routed through a tandem office, toallow network planners to design trunk upgrades between the variousoffices and/or to plan the addition of new offices.

[0078] It is a feature of the invention that at least one of the serversrunning analytical programs constitutes an on line analytical processingmeans providing a multidimensional database, wherein relational filesand AMA information relating to call set up and tear down are processedto consolidate and summarize successful and unsuccessful attempts toroute calls and provide reports thereof.

[0079] Additional objects, advantages and novel features of theinvention will be set forth in part in the description which follows,and in part will become apparent to those skilled in the art uponexamination of the following or may be learned by practice of theinvention. The objects and advantages of the invention may be realizedand attained by means of the instrumentalities and combinationsparticularly pointed out in the appended claims.

BRIEF DESCRIPTION OF DRAWINGS

[0080] The drawing figures depict the present invention by way ofexample, not by way of limitations. In the figures, like referencenumerals refer to the same or similar elements.

[0081]FIG. 1 is a diagrammatic illustration of a public switchedtelephone network showing its relation to an SS7 common channelinteroffice signaling network, a competitor or certified local exchangecarrier (CLEC), an Internet Service Provider (ISP), and the Internet.

[0082]FIG. 2 is a block diagram of a Public Switched Telephone Networkand its SS7 signal control network.

[0083]FIGS. 3 and 4 illustrate in graphic and tabular form respectivelythe protocol of an SS7 data signal.

[0084]FIGS. 5 and 6 provide an illustrative breakdown of an IAM.

[0085]FIG. 7 is a diagrammatic illustration of the network system ofFIG. 1 enhanced in a manner to implement unique and novel features ofthe present invention.

[0086]FIG. 8 is a diagrammatic illustration of a network systemaccording to another preferred embodiment of the invention arranged tomonitor and analyzed the operation of a tandem switch in relation to itsnetwork environment.

BEST MODE FOR CARRYING OUT THE INVENTION

[0087] Because the functioning of the invention is dependent upon theinformation which may be obtained from the operation of the SS7 commonchannel interoffice signaling network, a detailed description of theoperation of that network is believed helpful. Those familiar with thatoperation may desire to proceed to the next section of thespecification.

[0088] Referring to FIG. 2 there is shown a block diagram of a publicswitched telephone network and the SS7 network that is used to controlthe signaling for the switched network. Thus an analog switchedtelephone network is generally indicated at 10 having a common channelsignaling network in the form of an SS7 network illustrated generally at12. The switched telephone network consists of a series of centraloffices which are conventionally referred to as signaling points (SPs)in reference to the SS7 network. Certain of these SPs comprise endoffices (EOs) illustrated at 14, 16, 18 and 20 as EOs 1-4 in FIG. 2.Each signaling point has a point code comprising a 9-digit code assignedto every node in the network. In FIG. 2 EO1 has a point code of246-103-001, EO2 has a point code of 246-103-002, EO3 has a point codeof 255-201-103, and EO4 has a point code of 255-201-104.

[0089] The end offices EO1 and EO2 represent end offices in the regionof one regional operating company while end offices EO3 and EO4represent end offices of the region of a different operating company.Each operating company has its own network ID, shown here as 246 for theleft region and 255 for the right region in FIG. 2. The number 103 inthe designation 246-103-001, is the number of the cluster. A cluster canhold 32 SPs or members, the member being designated by the final 3numbers. Thus 246 may represent C & P of Virginia Regional OperatingCompany, cluster 103, member EO2 for EO2 when viewed from an SS7standpoint.

[0090] The broken lines connecting the SPs together may be analog trunksor voice or similar circuits. The SPs in a given region are connectedtogether by local trunks 22, 24 and 26 in the left region and 28, 30 and32 in the right region. The SPs in one region are connected to the SPsin other regions via inter-exchange carrier network trunks or ICN trunks34 and 36 in FIG. 2 connected to Access Tandems (ATs) 38 and 40 (AT1 andAT2). These SPs or ATs are shown as having point codes 246-103-003 and255-201-101 respectively.

[0091] Referring to FIG. 2, the SS7 network 12 comprises a series ofSignal Transfer Points (STPs) shown here at 40, 42, 44 and 46 designatedSTP1, STP2, STP3 and STP4. Each STP in a network is connected to the SPsin the network by A links indicated at 48, 50, 52 and 54. STP1 and STP2constitute a mated pair of STPs connected by C links 56 while STP3 andSTP4 constitute a mated pair connected by C links 58, each mated pairserving its respective transport area. It will be understood that theremay be multiple mated pairs per region, one for each designatedtransport area. STP1 is connected to STP3 by B link 60 and to STP4 by Dlink 62. STP2 is connected to STP4 by B link 64 and to STP3 by D link66.

[0092] As will be understood, the A, B, C and D links are physicallyidentical with the designation relating to cost in terms of ease ofaccess. The A links represent the lowest cost. B and D links have thesame route cost with respect to SS7 so that the D designation is usedonly because it extends diagonally in the drawing. The C links are usedto communicate between the two paired STPs for network managementinformation and also constitute another route. The STPs in mated pairshave the same translations. Thus the translations in STP1 are the sameas the translations in STP2, and the translations in STP3 are the sameas the translations in STP4. The C links communicate between the pairedSTPs for network management information and SS7 message routing. The STPpair cannot function without the C links. Therefore, unnecessaryutilization of the C links causes congestion and prevents the pairedSTPs from performing their intended function.

[0093] The STPs are connected to Signal Control Points (SCPs) indicatedin FIG. 2 as an SCP 68 and an ISCP 70. The ISCP Is an IntegratedSignaling Control Point, which is basically the same as an SCP butcomprises a larger and more powerful computer. AIN may also be regardedas another ISCP. SCPs are usually used for 800 and credit card serviceswith ISCPs being used for AIN. However, this is optional. The ISCP mayhold application information as well as routing information whereas anSCP contains routing information, i.e., routing tables.

[0094] The SS7 network constitutes a highly redundant data network,generally a 56 K switched data circuit. By way of example, an SS7message from EO2 to EO4 might travel any one of 8 possible routes. Itcould go from EO2 to STP1, from STP1 to STP3, STP3 to EO4. One variationon that route would be from STP1 down the D link 62 to STP4 to EO4, andso forth. In the event that a link between STP3 and EO4 was lost, an SS7route could be established from EO2 to EO4 via STP1 to STP3 and then viaC link 58 to STP4 to EO4. However, that would be an undesirable route inunnecessarily using the C link. A links provide direct connectivitywhile C links provide circuitous routes using extra switches, asituation to be avoided. An alternate route would be from STP1 via Dlink 62 to STP4 to EO4. Another reason for not using the C link is toavoid tying up the entire STP3-STP4 pair.

[0095] The operation of placing a call from EO2 to EO4 may be describedas follows: The user at EO2 picks up his phone and dials the number thatresides in EO4. The SP generates an Initial Address Message (IAM). Thismessage would have the destination point code of EO4, namely, point code255-201-104. it would have an originating point code of EO2, namely,246-103-002, in addition to miscellaneous other information needed forcall set-up. That message would then be sent to either STP1 or STP2.Assuming that the message goes to STP1, STP1 would look at the messageand determine that the message was not for it as an STP but rather isfor EO4. STP1 would then investigate possible routings to get to 255 orEO4. B and D links are available and STP1 would choose one of the two.Assuming that it chooses the B link to STP3, STP3 repeats the sameprocedure. It determines that the message is for 255 or EO4 and putsthat message on the A link to EO4.

[0096] EO4 gets the IAM which has the called telephone number in it anddetermines whether or not the line is busy. If the line is not busy, EO4generates an Address Complete Message (ACM) to indicate that it receivedthe request for a call and that the number is not busy. That message issent back by simply reversing the point codes. Now the destination pointcode is EO2 and the originating point code is EO4. The message goes backto EO2 to indicate that the IAM was received and processed. As soon asthe phone is answered at EO4, 204 sends an Answer Message (ANS) back toEO2 indicating that the phone at EO4 was picked up, and at that time thetrunks are connected together. EO2 connects its user to that trunk andEO4 connects its user to that trunk so that communication isestablished. All such messaging may occur in about 600 millisecondswhich would be average but not necessarily fast.

[0097] The foregoing constitutes the function of the STPs insofar asrouting is concerned. The STPs look at a point code and if it is not forthem they just pass it on via a route determined from translations androuting tables. The C link is the last route permitted and is notutilized unless no other route is available.

[0098] As opposed to the foregoing, where the point code was for EO4 andnot STP1, the point code may be for STP1. One example of such asituation would be the case of an 800 call. The 800 number is afictitious number which is associated with a POTS number in a databasein the SCP. Thus if EO2 makes an 800 call to EO4 it is necessary todetermine the real telephone number. EO2 launches a Switching ConnectionControl Park (SCCP) message, which is a database request. This pointcode has a destination point code of an alias which is the point code ofSTP1 and STP2. STP1 and STP2 have various point codes indicated in FIG.2 as 246-100-000 and 246-101-000. They also have alias point codes thatindicate that they have a function to perform. Upon recognizing such apoint code the STP does a data search and generates another SCP messageto perform a database dip. This returns the real telephone number andthe STP now has the destination point code of the real telephone numbermessage. This is sent back to EO2. STP1 determines that this message isnot for me but for EO2. The message is sent back down to EO2. EO2 nowhas a real telephone number and the system performs the IAM and ACMprocedure all over again to set up the call. The only difference betweena regular direct call and an 800 call is the necessity to perform thedip to obtain the real number first. This procedure takes about 1.3seconds because of the additional operation. The STPs have variousdatabases, such as the 800 database and the credit card database, andthere is still a further database for AIN.

[0099] The SS7 protocol describes how the signal messages are built androuted and provides for network management of the SS7 network itself.Thus if a link between EO4 and STP3 were to be lost, STP3 generates atransfer restricted message (TFR) to all nodes, i.e., all SPs connectedto STP3, indicating that traffic is not to be sent to STP3 for EO4because no route from STP3 to EO4 exists. If both A links to EO4 weredown, EO4 would essentially be isolated and the STP pair STP3 STP4 wouldbroadcast a transfer prohibited (TFP) message indicating that nothingshould be sent to the pair for EO4.

[0100] In the transfer restricted situation it would be possible forSTP3 to reach 704 via the C link to STP4. This is a non-favored routebut would be used in necessity. Handling such situations is the purposeof network managing messages. Congestion control or TFC accomplishesbasically the same thing except that it constitutes a more sophisticatedmessage limiting use of a circuit by stopping messages below a certainpriority. Each message has a different priority. IAMs have a priority of1 where ANS messages have a priority of 2.

[0101] Upon congestion occurring in the STP node for EO4 a new callcould not be sent to EO4 because it constitutes a priority 1 messagewhich is restricted because the congestion level is 2. Only priority 2messages and higher would be permitted. If a call is already existing itcould be answered or released. Releases have a priority of 2 to permitcall completion. New calls could not be initiated until the congestionhad been removed or lowered to congestion status 1 or 0.

[0102] The SS7 network constitutes a sophisticated network having a highpredictability which is spelled out in the predetermined protocol. Ifall facts regarding the network are known it is possible to predict whatwill (or should) occur next. The system and method of the presentinvention is predicated upon recognition of that fact.

[0103] The SS7 messages traverse the network at all times. The messagesthemselves comprise digital serial messages that come into the STP. Thestart of the message is identified by a flag which is a zero followed by6 ones and another 0. This constitutes a unique bit pattern in the SS7protocol. The protocol ensures that this particular pattern is notrepeated until the next message. This provides a flag at the beginningof a new message. A flag at the end of a message is also providedusually in the form of the flag at the beginning of the next message,i.e., a message usually contains only one flag. The message is arrangedin 8 bits or in octets. These octets represent the information carriedby the message. The message contains both fixed and variable parameters.The Message Transport Part (MTP) of the SS7 message is always in thesame place. The values change but the MTP is always in the same place.

[0104] Referring to FIGS. 3 and 4, the start of a message is indicatedat 72 with the commencement of the flag 74. The first 7 bits followingthe flag constitute the Backward Sequence Number (BSN). The eighth bitis the backward indicator bit which is used to track whether messageshave been received correctly. The backward sequence number was theforward sequence of the other node's message when it was sent. Referringto FIG. 2, if EO2 sends a message to EO4, EO2s include a ForwardSequence Number (FSN) in the 3rd octet of its message. Upon receivingthis message, EO4 will include a Backward Sequence Number (BSN) equal tothe FSN sent in the previous message in its next message to EO2. Thisindicated to EO2 that EO4 received the first message. This constitutes apositive acknowledgment of receipt of a message. If the eighth bit ofthe second octet or Backward Indicator Bit (BIB) is inverted, itindicates a failure to receive the identified message. If the 8th bit inthe 2nd octet, Backward Indicator Bit (BIB), is inverted, it tells thereceiving node that the identified message was not received. Theaccompanying BSN represents the last message that was received. Thereceiving node will then invert its Forward Indicating Bit (FIB), 8thbit of the 3rd octet, acknowledging a retransmission remission request,and will begin to send the missing messages until the transmitting endsuccessfully acknowledges all remaining messages, i.e.:

[0105] EO2 sends a message with a FSN of 5 to EO4;

[0106] EO4 transmits a message back to EO2 with an inverted BIB and aBSN of 2, indicating that was the last message it received;

[0107] EO2 then inverts its FIB and retransmits message 3;

[0108] If EO4 acknowledges this message correctly (BSN of 3) EO2 willretransmit message 4 and then 5.

[0109] Thus between the BIB and FIB and BSN and FSN, the STP keeps trackof all of the messages sent between the two nodes at each end of a link.This provides predictability. If a node fails to receive anacknowledgment within a predetermined period of time it will take thelink out of service because it is receiving no acknowledgments. This isusually a short period of time such as 1.6 seconds.

[0110] Every 8 bits represents another part of the message until the endof the message. At about the fourth octet there is a length indicator toindicate the length of the message. In this case the message is bad inthat it indicates six which is not a complete message. Assuming acomplete message where the length indicator indicates 23 octets, thisprovides another means for error detection. Thus if the recipient countsto 28 this indicates that something is wrong and the message is sentagain.

[0111] Octet 5 is the Service Information Octet (SIO). This indicateswhether it is a Fill In Signal Unit (FISU), Link Service Signaling Unit(LSSU) or Message Signaling Unit (MSU). MSUs are the only ones used forsetting up calls or 800, LSSUs are used for alignment, and FISUs arefill in signals. Thus an LSSU is seen only if the link is out of serviceand going back into service or going out of service.

[0112] Octets 6-11 contain the point codes. Thus the point code235-81-8198 is the point code which would be read in FIG. 3. This isbackwards as it comes from the message which arrives number, cluster,network ID in the order of bits received. That constitutes the routinglabel telling the STP and the nodes where the message came from andwhere it is going. Other parameters are involved depending upon the kindof message. If this were a FISU, that would be it. There would be 16other bits that have Cyclic Redundancy Codes (CRCs) in them and anotherflag which would constitute the end. CRCs constitute a further errordetection code which is a legal 1 function in the protocol. From theforegoing it will be seen that the messages contain various fields.

[0113] This describes the basic format of an SS7 message which is thesame for all messages. FIGS. 5 and 6 provide an illustrative breakdownof an IAM. FIG. 5 indicates the various fields that may exist, such asnature of connection, forward indicators, calling party category, etc.Following this are variable parameters such as pointers to another partof the message where other data is located.

[0114] Referring to FIG. 1 there is shown a diagrammatic illustration ofa typical public switched telephone network (PSTN) having an SS7 commonchannel interoffice switching system fitted with one embodiment of asystem for carrying one feature of the invention. FIG. 1 shows aCertified Local Exchange Carrier (sometimes referred to as a competitorlocal exchange carrier) connected to the main PSTN. Referring to thatfigure there are seen typical end office switching systems 110 and 112connected by a direct trunk 114. The central office switches 110 and 112typically consist of programmable digital switches with CCIScommunications capabilities. One example of such a switch is a 5ESS typeswitch manufactured by AT&T; but other vendors, such as Northern Telecomand Seimens, manufacture comparable digital switches which could serveas the SSPs and SPs. The SSP type implementation of such switchesdiffers from the SP type implementation of such switches in that the SSPswitch includes additional software to recognize the full set of AINtriggers and launch appropriate queries in an Advanced IntelligentNetwork (AIN) CCIS system.

[0115] In addition to being connected by the illustrative directtrunk(s) 114, the end office switches 110 and 112 are also connected viaan illustrative tandem switch 116. The North American telephone networkrelies on the concept of overflow routing when call demand between endoffices exceeds capacity. This extra demand is routed through aspecialized switch called a tandem. Tandem switches generally have nosubscriber lines, only trunk circuits. These trunks may be from endoffices within the local area of the tandem or from otherinterconnecting networks. Since several end offices (50 or more) mayhave their overflow trunks connected to the tandem, the tandem acts as ashared spare capacity for all its subtending end offices. A tandem alsoacts as an access switch where other networks, such as another regionalPSTN or a CLEC, will hand off calls to the local carrier. Other than thefact that tandem switches serve only trunks, their construction andoperation is similar to the end office switches described above.

[0116] The end office switching systems serve subscribers through localloops which typically comprise twisted pair. The end office 110 isillustratively shown serving a telephone terminal 118 and a personalcomputer (PC) 120, while the end office 112 serves a telephone terminal121 and an Internet Service Provider (ISP) 122. The ISP is usuallyconnected to the serving office by a multiline hunt group which isoptimally of a size adequate to handle the volume of calls to beexpected. The ISP is connected to the Internet shown as a cloud 124.

[0117] The switching systems in the public switched telephone networkare connected by CCIS data links shown as broken lines between pairedsignal transfer points (STPs) 126 and 128 and the switching systems 110,112, and 116. In FIG. 1 the PSTN is coupled to a Certified LocalExchange Carrier 130 by SS7 CCIS B and D data links from STPs 126 and128 to STPs 132 and 134. The two networks are also connected by anillustrative trunk 136 connecting tandem switches 116 and 138. The CLECSTPs 132 and 134 are connected by SS7 A links to the tandem switch 138and to an illustrative CLEC end office switch 140. The CLEC end office140 is shown as serving another ISP 142.

[0118] According to the invention the public switched telephone network(PSTN) is provided with a traffic monitoring and analyzing systemcomprising monitors and processors or servers of the type described indetail in the above discussed Pester patent. Referring to FIG. 1, themonitors or interfaces to the SS7 links are shown coupled to the A linksbetween the STPs 126 and 128 and switches 110, 112, and 116 at 144.These monitors or interfaces to the links may be of the type describedin the referenced Pester patent. The monitors or interfaces may beconductively or non-conductively coupled to the links to serve aspassive interfaces. The monitors are associated with each of the A linksto the relevant switches, and are coupled to card cages 149 as shown inthe Pester patent.

[0119] The card cages 146 are connected to a site processor and storage148-150, the processor 150 is accessed and controllable by that computerstation. In the system described in the Pester patent such a system isutilized to perform surveillance and control of the signaling network toprevent system failures, and to perform other functions such as frauddetection. Such a system is shown in a fraud detection and event controlconfiguration in copending, allowed Chacainias, McDermott and Farrisapplication Ser. No. 08/510,931, titled Common Channel Signaling EventDetection and Control. That application is incorporated herein byreference in its entirety. However, the system shown in FIG. 1 serves adifferent purpose as will be described in detail. It is intended thatmultiple systems of this type serving different purposes mayadvantageously exist in the PSTN, although only a single system is hereillustrated for purposes of simplicity and clarity.

[0120] The SS7 A link signaling in a completed call typically includesan Initial Address Message (IAM), an Answer Complete Message (ACM), anAnswer Message (ANM), Release Message (REL), a Release Complete Message(RLC), and the various other elements described hereinabove. Since theCCIS system is intentionally redundant, the messages in a related setmay be routed over different A links. It is therefore necessary toreassemble the signaling pertaining to a desired transaction orsignaling set, such as a single call to provide one call detail recordor CDR. This is accomplished in the site processor 148 in a known manneras described in the Pester or Brockman et al patents.

[0121] With the reassembled message sets the site processor has the datato show the called and calling stations, the time of the call, theelapsed time of the call, and various other detailed data. By monitoringthe SS7 signaling for all of the calls terminating in a designatedswitch, such as the switch 112, and knowing the number for the ISP, itis possible to gather all of the desired information about calls goingto the ISP 122 via an interswitch path. It will be understood that callscompleted through a single switch, such as a call from telephoneterminal 121 through end office switch 112 to ISP 122, will not generatethis type of CCIS signaling and thus will not be reflected in the abovediscussed SS7 signaling. The assemblage of the data desired for aparticular purpose occurs at the site processor level and is undercontrol of the computer station 150.

[0122] Referring to FIG. 7 the site processors for the SS7 network 210are shown at 212, 214, and 216. These site processors represent siteprocessors of the type shown at 148 in FIG. 1 and serve in the samecapacity. The flat files produced by these processors are delivered tothe Telco WAN (wide area network) and from the WAN to a central SS7 CDRflat file server. The server 220 provides a relational database for thecollected SS7 flat files. Its primary function is to collect and storecall records/CDRs sent from the site servers. It preferably should beconfigured to tabulate and process defined traffic measurement and userreports in HTML format accessible from a Web Browser interface.

[0123] As was pointed out hereinabove, the site processors are capableof assembling and processing information with respect to inter-switchcalls but do not handle intra-switch calls. In order that all trafficmay be monitored and analyzed it is a feature of one embodiment of theinvention to utilize Automated Message Accounting (AMA) data. As will beunderstood by those skilled in the art, AMA equipment records calldetails at each stage of a connection. The calling and called partynumbers are registered initially. An answer entry registers the time ofconnection, and the terminating entry registers the time of disconnect.These entries are linked by a common identifying number to distinguishthem from other calls on the storage medium. This data is processed atmessage processing servers (MPS) where the entries are assembled intocompleted messages and incomplete messages are analyzed foradministrative purposes and fraud detection. The AMA equipment alsoregisters local measured service billing details which may be sent to aRevenue Accounting Office (RAO). AMA is here used to refer to thenetwork functionality that measures collects, formats, and outputssubscriber network usage data to upstream billing operating systems andother operating systems (OS). The AMA network is shown in FIG. 7, at 222and an MPS is shown at 224. The MPS delivers the processed AMA call datato the Telco WAN 218. The Telco WAN delivers the data to a central AMAserver 226 where relational databases are maintained. The servers 226and 220 are linked by a fiber distributed data interface (FDDI) 228,which enables free exchange of information and processing between thetwo servers.

[0124] According to a preferred embodiment of the invention the servers220 and 226 and their relational databases are connected to a processoror server and OLAP database 230. As will be understood by those skilledin the art, an OLAP processor and database is an OnLine AnalyticalProcessing Database designed for fast access to summarized data. Usingspecialized indexing techniques, it processes queries that pertain tolarge amounts of data and multidimensional views of data much fasterthan traditional relational databases. Among other things it provides anExecutive Information System (EIS) that consolidates and summarizesongoing transactions within a system to provide a data warehouse.

[0125] One fact table is surrounded by a series of related tables whichthe processor is capable of “drilling into” to obtain additionalinformation. Software providing this capability is available from GentiaSoftware, Inc. of Wakefield, Mass. under the product name of Gentia DB.Gentia DB is a fully OLAP-compliant multidimensional database. Similarto Essbase, it is loaded with data derived from various company datasources, and is preconsolidated. Gentia supports an “unlimited” numberof dimensions, as well as multiple hierarchies within a dimension. It isa fully object oriented visual development environment, with a libraryof predefined objects, and provides an OLAP database with tools forloading, analysis, querying, and reporting.

[0126] Gentia runs on multiple platforms and is scalable across a largesystem. While the program has been described as running on the standalone processor 230 in FIG. 7, it could be run on either or both of theservers 226 and 220, which communicate through the FDDI 228. The server230 is accessed by multiple user work stations 232, 234 and 236. It iscapable of serving as an interface to the Internet and, in theillustrated example, interfaces to the Telco intranet or WAN 218. Theserver 230 also interfaces to the switches in the PSTN via a datacircuit 238 and is capable of drilling down into switch stored data. Forexample, the OLAP server 230 is capable of retrieving switch storeddata, such as office equipment (OE) numbers. Access to the OLAPprocessor and database is available from the Telco intranet.

[0127] For a study of the calls to the ISP 122, the card cages are setup to monitor all of the A links into the end office switch 112, whichis the switch that serves the ISP. Initially all of the relevant SS7messages off of those links which are directed to the number for thatISP are trapped at the site processor 148. This includes all of thosemessages including busy and no answer in addition to the messagespertaining to completed calls. Since those messages contain a largequantity of information it is possible to derive quite detailed analysisdata.

[0128] Preferably the collected call records will contain the followinginformation:

[0129] a.) Whether the call is terminating or originating

[0130] b.) The total carrier elapsed time (time between IAM and REL)

[0131] c.) The total customer elapsed time (time between ANS and REL)

[0132] d.) Whether the call was answered and how it was cleared (i.e.,busy, normal clearing, etc.)

[0133] e.) The date and time the call began

[0134] f.) The originating and terminating number

[0135] This data is then preferably aggregated into periodic reports.Once each period, when the above data is assembled, it is processed andcompressed into flat files for each ISP containing the following data:

[0136] a.) For every hour from midnight to midnight the number of callsattempted that hour, the average call holding time for calls that beganin that hour, and the total MOU for calls that began in that hour.Additionally, the average CCS/MS will be calculated for the 24 hourperiod and the percent of total terminating MOU destined for theparticular ISP in the 24 hour period. The CCS/MS is hundred callsseconds per main station. This is a standard measure of usage for a mainstation in an hour, with a range from 0 (no measured use in an hour) to36 (line in use for full 60 minutes). The average CCS/MS represents thesum total of all the calls and their lengths of time that collectivelymake up usage during the busy hour, divided by the applicable number ofworking main stations.

[0137] b.) Each NPA NXX XXXX that called the ISP during the day. Foreach line number the report will indicate the total customer connecttime for the day for that customer and the average call holding time(number of calls divided by total MOU). The report will only include the100 highest users.

[0138] A summary report will also be generated for the day identifying:

[0139] a.) The percent of the total MOU for the switch that was destinedfor all ISPs

[0140] b.) The percent (by MOU) of traffic destined to ISPs byoriginating offices.

[0141] A third report will identify the following statistics for amaximum of 300 randomly selected numbers:

[0142] a.) The average call holding time for each number

[0143] b.) The total MOU for the 24 hour period for each number

[0144] c.) The average CCS/MS for each number

[0145] The foregoing reports will be generated each 24 hour period andwritten to a disk file in text form. A second report will be generatedwriting all data to a file in a comma separated list that is suitablefor importing into most spread sheets. Additionally, the data will bewritten in html format file for display using any Wed Browser. Thelatter interface will require http Web Server software at the remotesite as well as access to the corporate network.

[0146] Thus the site processor collects a large amount of raw data fromwhich it assembles call detail records (CDRs), and then extracts thatdata which is desired for the particular analysis to be made.

[0147] In this example all of the calls bound for switch 112 arecaptured, the call records are assembled into call detail records(CDRs), and then stored in flat files. The flat files are then sent tothe work station 150, and the desired analysis is performed at the workstation.

[0148] In the foregoing discussion it was assumed that the ISP waspre-identified. While the major point of presence for the larger ISPs(SprintNet, STTWorldnet, AOL) may have been known , there has been verylimited data available to effectively engineer and administer for thetraffic load to lesser known ISPs. Further, there is very littleunderstanding of how CLECs and ISPs themselves are redirecting hugevolumes of traffic bound for the Internet across PSTN tandem and IOFnetworks. It is a feature of this invention that a method of locatingand identifying such ISPs is provided.

[0149] A preferred methodology for implementing ISP identification andlocation may be accomplished in the following manner.

[0150] 1. Designate an end office switching system that is known to beencountering some congestion.

[0151] 2. Program the monitoring and analysis system illustrated in FIG.1 to collect CDR data for that switch during designated hours known tobe peak traffic hours. In the system illustrated in FIG. 1 the endoffice 112 may be selected.

[0152] 3. Trap all calls bound for office 112 during the designatedhours.

[0153] 4. Assemble the CDRs from the collected data and process andcompress that data to form CSV (comma separated values) flat files.

[0154] 5. Store these flat files in the site processor storage 148.

[0155] 6. Convert these files to a full featured spread sheet which canlink multiple spread sheets for consolidation, such as Excel.

[0156] 7. Perform a statistical analysis and determine which numbers hadthe most calls made to them, which calls had the most minutes of use,and which calls had the longest hold times.

[0157] 8. Call the numbers thus identified and ascertain which areanswered by modems. These represent ISPs.

[0158] 9. Identify the numbers of the parties which called those numbersin the analysis. These are users of the respective ISPs. The informationis available from the CDRs.

[0159] 10. Identify the locations of the users and associated end officeswitches from Telco records.

[0160] The information obtained from this analysis will provide anindication of the routes experiencing difficulties and enable strategicplanning to eliminate or at least ameliorate the difficulty. Forexample, attempts may be made to have distressed users install ADSL orXDSL equipment. Alternatively or conjunctively a Telco data link, suchas X.25 or other equivalent, may be established between the end officeestablished as handling the bulk of the overload calls to the ISP.

[0161] Turning attention to the CLEC, telecommunication carriers areentering PSTN markets and buying unbundling network services at anaccelerated rate. Frequent and detailed measurement of this new trafficis highly desired from the PSTN standpoint to optimize local switch andIOF/tandem design and to effectively plan and implement PSTN off-loadstrategies. In the case of analyzing the traffic to the CLEC 130 themonitoring takes place on the C and D links between the STP pairs 126and 128 on the one hand, and 132 and 134 on the other. In each case themonitoring and analysis is completely transparent to the trunk circuitsand the customers. However the traffic which is being investigated andmonitored is the traffic on the trunks where the overload is likely tooccur. That is, while the signaling traffic is being monitored it is notthe signaling traffic itself that is a matter of concern. On the otherhand it has been found that it is possible through appropriate analysisof the signaling traffic data to determine not only that a call did notcomplete but also the point at which it failed, i.e.,, the point ofcongestion. The release code shows that the release was due to networkcongestion. In the case of a CLEC every call made is interoffice so thatone hundred percent of PSTN/CLEC. calls may be monitored using the SS7signaling.

[0162] The foregoing monitoring and analysis of the CLEC traffic may beimplemented by monitors on the B and D links. Such monitors are shown inFIG. 1 at 152 connected to card cages 154. The card cages in turn areconnected to the site processor and storage 155 and 157.

[0163]FIG. 1 illustrates the installation of that portion of the systemof the invention which is local to the pair of STPs 126 and 128. Thesite processor is typically housed with an STP. This site system ispreferably dedicated to the traffic control purposes of this invention.That is, the monitors, card cages, and site processor are not common toany similar equipment which might be used by the PSTN signaling ornetwork surveillance, fraud detection, event detection, or similarpurposes. Control of local installations which are distributed about thePSTN network, such as the installation shown in FIG. 1, is centralizedaccording to the preferred embodiment of the invention, and providesenhancements and additional functions to those that are capable of beingimplemented by the local installation(s).

[0164] In summary, the system shown in FIG. 7 will collect, integrateand compress call record data continuously from across the PSTNswitching network. Data from two primary sources, namely, SS7 messagingand AMA billing records, will be processed real time off of variousregional platforms and routed to a central server where the call recordswill be stored in a transactional relational database. Through anetworked analytical software application running on the database, usersof the system will be able to create detailed interactive reports, orperform “on the fly” analysis. The system will be configured in aclient-server architecture, with a limited user group. However, thesystem is so designed as to be readily scaleable by users and datavolume, expandable to Web Browser interface, and readily integrated withother PSTN databases and platforms.

[0165] Needs that will be satisfied by this system include thefollowing:

[0166] a.) End Office Load Balance Process Support—The system willprovide an expedient, flexible, accurate, and cost effective method toidentify individual high usage lines contributing to blockage. Theinformation will eliminate the need to perform costly, untimely SLUstudies and reduce the number of Line Equipment Transfers required toaddress office load balance concerns.

[0167] b.) Tandem/Trunk Planning Resource—Unbundling and the increase inCertified Local Exchange Carriers are increasing the necessity fortandem switch growth. Effective growth must be dependent upon knowingcustomer calling patterns, communities of interest and points or originand destination. The new system will provide the tools to adopt aproactive approach that will provide a long term economic solution forserving future demand.

[0168] c.) Internet Service Provider (ISP) Studies—ISP traffic analysisperformed with the system will provide the PSTN with a means to monitorISP traffic patterns on a per ISP/switch basis, and enable the PSTN tobetter serve ISP customers while maintaining optimal networkutilization. The system will also provide unique detailed information onthe location and calling characteristics on heavy Internet users.

[0169] Referring to FIG. 8 there is shown an architecture suitable formonitoring and analyzing the performance of a tandem switch, such as thetandem 116 in the PSTN in FIG. 1. All calls that are switched through atandem produce two records, one for the trunk setup to the tandem, andanother for the trunk setup out of the tandem. The first call record,the setup into the tandem, contains the originating point code whichidentifies the originating switch. It also contains the called party NPANXX which identifies the terminating switch except in the case where theLEC tandem delivers the call to another tandem. Since the second tandemis not identified by an NPA NXX there is no way to determine thedestination of tandem to tandem calls. Fortunately, this condition onlyhappens regularly when a call is sent to, or received from, anothercarrier which means that end office to end office overflow will beavailable. This call record also only contains the incoming trunkidentifier, the outgoing trunk information is contained in the secondpart of the call which is not recorded.

[0170] Referring to FIG. 8 there is shown a tandem switch 116 whichsubtends or links a large number of end offices, here shown as officesor switches 300-1 to 300-n and 302-1 to 302-n. These end offices 300-1to 300-n and 302-1 and 302-n are connected to the tandem 116 by trunkgroups illustratively shown by the heavy lines 304 and 306. Each of theswitches is connected by A links to an STP pair 308 and 310. The A linksare shown at 312, 314, 316, 318, and 320. The A links are provided withmonitors shown at 322 connected to card cages 324. The card cages areconnected to one or more site processors 326-328. The site processor(s)are connected to the Telco WAN 218 shown in FIG. 7. The end offices 300and 302 are connected by direct trunk groups shown illustratively by theheavy line at 330.

[0171] An illustrative call from end office 300-1 to end office 302-1may be described as follows: When a subscriber goes off hook in endoffice 300-1 and dials to call someone served by end office 302-1, thecommon channel signaling link is first going to determine whether thedialed terminal is available. If so, it will signal to proceed with thecall. If all of the direct trunks 330 are busy, It will go back up tothe STP and report that condition. The STP will respond by telling theswitch 300-1 to set up a connection between itself and the tandem 116,and will tell the tandem to set up a connection between the tandem andend office 302-1. The STP knows all of the paths that it can map, andthrough its mapping capabilities it is going to know the number ofavailable direct trunks from 300-1 to 302-1, and it is also going toknow they are busy. So, once it knows that, then it will conclude thatit has to go to an alternate route. In this illustrative case the firstchoice is to route through the tandem office. It will just tell it toset it up, and it will do that through signaling to the respectiveoffices via A links.

[0172] Another reason for traffic studies is to relieve the tandemswitch itself, even though the call may be directed through that office.The system of the invention provides a means to analyze not only theload going through the tandem but also to analyze the routing within thetandem facility. There are historically a large number of T-1 systems orDS-1s to and from the tandem each providing 24 routes. Thus, while theremay be 24 trunks through the tandem, all of those trunks may not benecessary to handle this call. It may be feasible to loop the callthrough the tandem facility through a DAX, MUX or multiplexer 332without going through the switch itself. This will appear as a directconnection. The analysis of the invention will provide the data and highlevel analysis mechanism to provide concise reports to study thissituation.

[0173] From a basic standpoint it will take the total number of officessubtending the tandem and rank those offices to show which are makingthe most use of the tandem. This may involve analysis of three sets ofCCIS signaling: the signaling from the originating office to the tandem,the signaling from the tandem to the terminating office, and theoriginal signaling from the original office to the terminating office todetermine availability of the dialed terminal. All of this data can becaptured from the A link signaling and is subject to the high levelanalysis in the high level OLAP object oriented transactional processorillustrated at 230 FIG. 7. This provides information to indicate themost economical and efficient solution to the problem. The solution mayinvolve the provision of additional direct trunks, and in such asituation will provide information to indicate the particular endoffices which should be linked. Alternately, or conjunctively, this mayindicate that more trunk paths are desirable through the tandem. Theanalysis will also provide direction as to additional analysis andcollection of specific data from designated A links to provide anoptimum solution.

[0174] From the foregoing it may be seen that the system and methodologyof the invention provide a powerful and flexible tool for performingvarying investigations and surveillance. Thus, as examples, it isfeasible to identify ISPs, determine the source of the largest amount oftraffic to the identified ISPs, the reason for overloading, the optimalsolution to the overloading, analysis of tandem loading and overloading,determination of the largest causes of that overloading, and providing aranking of potential solutions to discovered problems.

[0175] While the foregoing has described what are considered to bepreferred embodiments of the invention it is understood that variousmodifications may be made therein and that the invention may beimplemented in various forms and embodiments, and that it may be appliedin numerous applications, only some of which have been described herein.It is intended by the following claims to claim all such modificationsand variations which fall within the true scope of the invention.

What is claimed is:
 1. In a switched telecommunications network havingend office switching systems controlled by a common channel signalingsystem connected to the end office switching systems and to pairedsignal transfer points, the method comprising: monitoring the signalingbetween the end office switching systems and the signal transfer pointsand selecting the signaling relating to transactions; collating theselected signaling by transaction; processing the collated signaling tocreate relational flat files relating to multiple transactions;subjecting the flat files to on line analytical processing to provide amultidimensional database to consolidate and summarize ongoingtransactions and provide reports thereof.
 2. A method according to claim1 wherein said transactions comprise completed dialed telecommunicationsessions between a calling terminal and a called terminal.
 3. A methodaccording to claim 2 wherein said transactions also comprise incompleteddialed attempts to establish telecommunication sessions between acalling terminal and a called terminal.
 4. A method according to claim 3including the step of providing a report of calls dialed to a designatedterminal in a designated time period.
 5. A method according to claim 4wherein said report includes data relating to the time of connection ofcompleted calls.
 6. A method according to claim 5 wherein said reportincludes data relating to the number of Uncompleted calls within a timeframe.
 7. A method according to claim 2 wherein said transactionscomprise completed dialed telecommunication sessions between a callingterminal and a called terminal, and including the steps of providing areport of calls dialed to a designated terminal in a designated timeperiod and data regarding the lengths thereof.
 8. A method according toclaim 7 wherein said transactions also comprise incompleted attempts toestablish dialed telecommunication sessions between a calling terminaland a called terminal, and including the steps of providing a report ofthe incompleted calls dialed to said designated terminal in saiddesignated time period.
 9. A method according to claim 7 wherein saidreport includes information regarding the routing of said calls.
 10. Amethod according to claim 9 wherein said report includes information asto whether said calls were routed through a tandem switching system. 11.A method according to claim 10 wherein said report includes informationidentifying the originating switching systems, the tandem switchingsystems, and the terminating switching systems for said calls.
 12. Amethod according to claim 11 wherein said report includes information asto whether said calls were routed through a tandem switching facilitywithout routing through the tandem switch.
 13. A method according toclaim 12 wherein said report includes information as to whether saidcalls were routed through the switch in said tandem switchinginstallation.
 14. A method according to claim 1 wherein said commonchannel signaling system is an SS7 system and said monitoring occurs onA links in that system.
 15. A method according to claim 14 wherein saidmonitoring occurs on A links to the originating switching systems and tothe terminating switching systems.
 16. A method according to claim 15wherein said monitoring also occurs on A links to a tandem switchingsystem connected between said originating and said terminating switchingsystems.
 17. A method according to claim 15 including the step ofproviding a report of calls dialed to a designated terminal in adesignated time period and including identification of the originatingswitching systems.
 18. In a switched telecommunications network havingend office switching systems controlled by a common channel signalingsystem connected by links to the end office switching systems and topaired signal transfer points, the method comprising: identifying an endoffice switching system observed to have encountered congestion;monitoring the links between the signal transfer points and theidentified switching system; trapping all common channel signalingbetween the signal transfer points and the identified switching systemfor a time period; processing the trapped signaling to form call detailrecords; processing the call detail records to determine which numbersserved by the identified switching system received the most calls withinthe time period; and calling the identified numbers and determine whichnumbers serve modems.
 19. A method according to claim 18 including thestep of identifying the numbers of terminals which originated calls tothe switching system identified as having received the most calls withinthe time period.
 20. A method according to claim 19 including the stepof determining the end office switching systems serving the originatingterminals.
 21. A method according to claim 18 wherein said call detailrecords include dialed calls which were not completed.
 22. A methodaccording to claim 18 wherein said processing of said call detailrecords includes on line analytical processing to provide amultidimensional database to consolidate and summarize ongoing calls andprovide reports thereof.
 23. In a switched telecommunications networkhaving end office switching systems controlled by an SS7 common channelsignaling system using packet switching via A, B, C, and D linksconnected to paired signal transfer points connected to one another by Dlinks and connected by A links to the end office switching systems, themethod comprising: monitoring the signaling in said A links andselecting the A link signaling relating to call set up; collating saidselected signaling by call; processing said collated signaling to createrelational files relating to multiple calls; subjecting the relationalfiles to on line analytical processing to provide a multidimensionaldatabase to consolidate and summarize ongoing call attempts andcompletions and provide reports thereof.
 24. A method according to claim23 including the step of providing a report of calls dialed to adesignated terminal in a designated time period.
 25. A method accordingto claim 24 wherein said report includes data relating to time ofconnection of completed calls.
 26. A method according to claim 25wherein said report includes data relating to the number of incompletedcalls within a time frame.
 27. A method according to claim 25 whereinsaid report includes information regarding the routing of said calls.28. A method according to claim 27 wherein said report includesinformation as to whether said calls were routed through a tandemswitching system.
 29. In a switched telecommunications network havingtrunked end office and tandem switching systems controlled by an SS7common channel signaling system using packet switching via A, B, C, andD links connected to paired signal transfer points connected to oneanother by C links and connected by A links to the end office and tandemswitching systems, the method comprising: monitoring the signaling insaid A links and selecting the A link signaling relating to call set upbetween end office switching systems through a tandem switching system;collating said selected signaling by call based at least in part on Alink signaling to and from said tandem switching system; processing saidcollated signaling to create relational files relating to multiplecalls; subjecting the relational files to on line analytical processingto provide a multidimensional database to consolidate and summarizesuccessful and unsuccessful attempts to route calls through said tandemswitching system and provide reports thereof.
 30. A method according toclaim 29 including the steps of providing reports of the identity of theend office switching systems from which calls were routed to said tandemswitching system.
 31. A method according to claim 30 including the stepsof providing reports of the identity of the end office switching systemsto which calls were routed from said tandem switching system.
 32. Aswitched telecommunications network having trunked end office and tandemswitching systems controlled by an SS7 common channel signaling systemusing packet switching via A, B, C, and D links connected to pairedsignal transfer points connected to one another by C links and connectedby A links to the end office and tandem switching systems, comprising;monitors interfacing to the signaling in said A links and selecting theA link signaling relating to call set up between end office switchingsystems through a tandem switching system; processing means collatingsaid selected signaling by call based at least in part on A linksignaling to and from said tandem switching system; processing meansprocessing said collated signaling to create relational files relatingto multiple calls; on line analytical processing means providing amultidimensional database, wherein said relational flat files areprocessed to consolidate and summarize successful and unsuccessfulattempts to route calls through said tandem switching system and providereports thereof.
 33. A switched telecommunications network according toclaim 32 wherein said online analytical processing means provides a datawarehouse including multiple related tables which said on lineanalytical processor drills into to retrieve additional information. 34.A switched telecommunications network according to claim 33 wherein saidon line analytical processor is object oriented.
 35. A switchedtelecommunications network according to claim 33 wherein at least partof said information is obtained from switching systems in said switchedtelecommunications network.
 36. A switched telecommunications networkaccording to claim 33 wherein at least part of said information isobtained from an automated message accounting system in said switchedtelecommunications network.
 37. A switched telecommunications networkaccording to claim 33 wherein at least part of said information relatesto calls completed through intra switching system connections.
 38. In aswitched telecommunications network having end office switching systemscontrolled by a common channel signaling system connected to the endoffice switching systems and to paired signal transfer points, andincluding automatic message accounting equipment recording call detailsof a connection transaction, the method comprising: monitoring thecommon channel signaling between the end office switching systems andthe signal transfer points and selecting the signaling relating toconnection transactions; collating the selected common channel signalingby transaction; collating automatic message accounting equipment outputrecording call detail; processing the collated common channel signalingand automatic message accounting output to provide a multidimensionaldatabase to consolidate and summarize ongoing transactions and providereports thereof.
 39. A method according to claim 38 wherein said lastnamed processing is performed at least in part by on line analyticalprocessing means providing a multidimensional database, whereinrelational data is processed to consolidate and summarize successful andunsuccessful attempts to route calls to completion.
 40. A methodaccording to claim 38 wherein said on line analytical processing meansextracts data from storages in said switched telecommunications networkin addition to said common channel signaling and said automatic messageaccounting equipment to provide said reports.
 41. A method according toclaim 40 wherein said storages at least in part comprise storageassociated with end office switching systems.
 42. A method according toclaim 41 wherein said extracted data relates to equipment associatedwith the switching system.
 43. A switched telecommunications networkhaving trunked end office and tandem switching systems controlled by anSS7 common channel signaling system using packet switching via A, B, C,and D links connected to paired signal transfer points connected to oneanother by C links and connected by A links to the end office and tandemswitching systems, said network including; monitors interfacing to thesignaling in said A links and selecting the A link signaling relating tocall set up between end office switching systems; processing meanscollating said selected signaling by call based at least in part on Alink signaling to and from said end office switching systems; processingmeans processing said collated signaling to create relational filesrelating to multiple calls; automatic message accounting equipmentrecording call details of call set up and tear down; on line analyticalprocessing means providing a multidimensional database, wherein saidrelational files and information relating to said call set up and teardown are processed to consolidate and summarize successful andunsuccessful attempts to route calls through said tandem switchingsystem and provide reports thereof.